Circuit interrupter construction



March 2, 1954 s. l. LINDELL 2,671,145

CIRCUIT INTERRUPTER CONSTRUCTION Filed Jan. 9, 1952 4 Sheets-Sheet lINVENTOR.

' March 2, 1954 I s. I. LINDELL 2,671,145

CIRCUIT INTERRUPTER CONSTRUCTION Filed Jan. 9, 1952 4 Sheets-Sheet 2INVENTOR.

j gwd ZZZ/2453a, BY

March 2, 1954 s, UNDELL 2,671,145

CIRCUIT INTERRUPTER CONSTRUCTION Filed Jan. 9, 1952 J41 J5 J4 4Sheets-Sheet 3 4 Sheets-Sheet 4 Z a 7 u W x .1 ww w 4% (I March 2, 1954Filed Jan. 9, 1952 6 6 m w fl wwww m w z 5 @50 w 4 \\f m. a Z y g y 6 ifX 1 l 1 MM 9% g 5 Zamaparerz 2640/2 a i it Patented Mar. 2, 1954 CIRCUITINTERRUPTER CONSTRUCTION lSigurd I. Lindell, Chicago, Ill., assignor toS & C Electric Company, Chicago, 111., a corporation of DelawareApplication January9, 1952, Serial No. 265,570

18 Claims.

JIhis inventionv relates, generally, to electric circuit'interruptersand it hasparticular, elation to circuituinterruptersrfor use in openingdisconnecting fuses, disconnectingiswitches, and the like Without arcingbetweenthe energized in making application Serial No. 254,036,.fi1edOctober 31, 1951, and assigned to the .assignee of this.application.

circuit without external-arcing; to restrain the biased apart contactsof thejcircuit interrupter from separating by inter-engaging .cshouldersthereon; to initiate operation of the-contacts. by movement of a sleeverelative to-a tubular housing containing the contacts; to provide a lostmotion connection between the sleeve andthe contacts so that the sameare free. to separate under the infiuenceof the means biasing themapart; to form the tubular housing of light transmitting arcextinguishing material so as to make the arc visible and to extinguishthe same; to provide for reclosing the contacts under load to provide acontact arm onthe circuit interrupter for engaging a pull ring or thelike on the dis connecting fuse or disconnecting switch and, to

For a more complete understanding of the na-,

ture" and belied to together which:

"Figur 1 is a'vi'ew in side'elev'ation of a conscope of this inventionreference may the following detailed'description taken withtheaccompanying drawings, in

ventional form of dropout fuse construction such as that described inmore detail in Ramsey United States Patent No. 2,247,700, issued July 1,1941, certain parts of the terminal assembly at the upper end beingbroken away in order to illustrate the details of construction;

Figure 2 is a top plan view of the circuit ,isolating device or dropoutfuse shown inFigurel;

Figure 3 is a view, in side elevation, ofthe dropout fuse constructionshown in Figure. 1, at a reduced scale, and illustrating the applicationof the auxiliary circuit interrupter of the present invention theretofor eiiecting the opening of. the fuse or disconnecting device withoutcausing arcing between the parts thereof last to separate;

Figures 4 and 5 are views, similar to Figure. 3, showing successivestages in th opening. of the fuse or disconnecting device by means ofthe auxiliary circuit interrupter;

Figure 6 is a View at an enlarged scale, certain parts being brokenaway, illustrating the general construction andarrangement of the.auxiliary circuit interrupter, the view being taken looking from rightto left with respect to the auxiliary circuit interrupter as illustratedin Figures 3, l and 5;

Figure 7 is a longitudinal sectional view of the auxiliary circuitinterrupter, the separable contacts being shown in the fully closedposition;

' Figure 8 is a detail sectional view taken generally along the line 3-8of Figure 7;

Figure 9 is a detail sectional view taken generally along the line 99 ofFigure '7;

Figure 10 is a view in side elevation of the tubular auxiliarycircuitinterrupter, the upperand lower ends being broken away, theconstruction shown being to illustrate more clearly .thelost motionconnection between the metallic sleeve slidably mounted on theinsulatingsleeve and the movable rod-like contact within. the circuitinterrupter;

Figure 11 is a longitudinal sectional view, similar to Figure '7,showing the relative positionsof the parts just after the contactswithin the circuit interrupter have separated; and

Figure 12is a view, similar to Figure '7, showing the relative positionsof the parts after the contacts in the circuit interrupter have beenmoved relatively to the full open position.

Referring now particularly to Figure l of. the drawings, it will beobserved that the reference character 10 designates, generally;acircuitrisoswitching device which, in; this instance, is a dropout fuseconstruction such-as described .in more'detail in Ramsey Patent No.

2,247,700, issued July 1, 1941, and referred to above. However, it willbe understood that the present invention can be used in conjunction withother circuit isolating devices, such as disconnecting switches in whicha switch blade is swung from the closed to the open position for thepurpose of introducing an air gap into the circuit.

The particular dropout fuse construction it includes an insulator Hwhich carries terminal assemblies 52 and i3 at its ends for connectionto line conductors as will be understood readily. Pivotally mounted at[4- on the lower terminal assembly !3 is a fuse tube that is indicated,generally, at H5. The fuse tube l5 contains a fusible element which isarranged to be ruptured on flow therethrough of excess current andmechanism is provided for automatically unlatching the fuse tube !5 fromthe upper terminal assembly l2 so that it can fall to the open circuitposition. When this occurs, the circuit is interrupted within the fusetube l5 and the arc incident thereto is extinguished. Ordinarily underfault conditions, the circuit will be interrupted within the fuse tubei5 before it swings out of contact with the upper line terminal assemblyit.

The present invention has to do particularly with the provision ofmechanism for effecting the opening of the circuit under load by bodilymoving the fuse tube l5 to the open circuit position while it stillcontains a fuse link that has not been ruptured by overcurrent.Provision is made for accomplishing this while load current is flowingthrough the fuse tube l5 in such manner that no arc is drawn between itand the upper terminal assembly l2 during the circuit opening operation.

At its upper end the fuse tube 55 has a fuse tube terminal assemblyindicated, generally, at [6. This assembly includes a sleeve I! that isslidable upwardly relative to the fuse tube i5 and formed integrallywith the sleeve ii is a hook is which is held in latching engagementwith a roller I9 carried by the upper terminal assembly 12. When thefuse link within the fuse tube is ruptured, the sleeve H is movedupwardly to such position that the hook is no. longer engages the roller!9. This same operation can be accomplished by means of an operating arm29 which is pivoted at 2| on the fuse tube terminal assembly I6. At itsouter end the operating arm 20 has a pull ring 22 which is arranged tobe engaged by the prong of a switch stick or the contact arm of theauxiliary circuit interrupted to be described hereinafter. When the pullring 22 is swung in a counterclockwise direction about the pivot 2!, thesleeve II is moved upwardly so that the hook is clears the roller I9.The fuse tube if: then can be swung or allowed to fall to the opencircuit position.

When the fuse tube I5 is operated in the manner just described by theprong of a switch stick engaging the pull ring 22, an arc will be drawnbetween the portions of the terminal assembly l2 and fuse tube terminalassembly 18 last to separate. As indicated above, such an arc may damageseverely these terminal assemblies or it may cause a fault on thecircuit. In accordance with the present invention, the fuse tube l5 canbe unlatched from the upper terminal assembly 12 and swung to the openposition without drawing an are between the terminal assemblies 12 and[6. The manner in which this is accomplished, generally, is by providinga shunt circuit between the terminal assemblies 12 and 16,

n outwardly,

unlatching the fuse tube terminal assembly it from the upper terminalassembly l2, swinging the fuse tube IE to such a position that an airgap is provided between the terminal assemblies [2 and i6 and theninterrupting the circuit by separating contacts within the auxiliarycircuit interrupter under such conditions that the arc is confined andextinguished quickly. The only modification required in the constructionof the circuit breaker Iii for accommodating the auxiliary circuitinterrupter comprises providing the sleet hood 23, forming a part of theterminal assembly I2, with a transversely extending conducting arm 24.As will appear hereinafter, this provides a fixed support for theauxiliary circuit interrupter while it is being employed for swingingthe fuse tube IE to open position without arcing between the terminalassemblies l2 and iii.

For the purpose of operating the dropout fuse EU to the open positionwithout arcing a generally tubular auxiliary circuit interrupter, showngenerally at 25, is provided. Its application to the dropout fuse I0 isillustrated in Figure 3 and the details of construction are shown moreclearly in Figure 7 to which reference now will be had.

It will be noted that the auxiliary circuit interrupter 25 has arelatively fixed conducting member 26 at its upper end to which ametallic cap 2? is secured by cap screws 28. A conducting eye member 29is pivoted or swiveled at 38 on the metallic cap 2? and it comprises apair of resilient contact extensions 3| which are bowed outwardly asindicated at 32 for facilitating entry of the transversely extendingconducting arm 2 carried by the sleet hood 23. In order to provide goodcontact engagement with the conducting arm 24, the upper portions 33 ofthe extensions 3! are positioned in side by side relationship and biasedtoward each other by the inherent resiliency of the contact extensions3|. Because of this construction, they grip the conducting arm 24tightly therebetween. The upper ends 34 of the contact extensions 3i areturned as shown, and interfit with a keeper 35 which not only limits themovement apart of the upper portions 33 but also serves as a stop toprevent relative movement between the eye member 29 and the conductingarm 24 when a downward pull is applied to the auxiliary circuitinterrupter 25 in a manner to be described.

With a view to resisting upward thrust on the conducting eye member 29,the resilient contact extensions 3! are bowed inwardly as indicated at36 for engaging the underside of the conducting arm 24. Sufficient lostmotion is provided between the upper portions 33 of the contactextensions 3i and the ends of the keeper 35 so as to permit these upperportions 33 to be moved sufficiently far apart so that the conductingarm 24 can pass between the innermost portions of the inwardly bowedportions 35. However, substantial force is required to effect thisrelative.

movement which ordinarily will be more than will be exerted forreclosing the contacts of the auxiliary circuit interrupter 25 in amanner to be described.

Again referring to the relatively fixed conducting member 25, it will beobserved that it is provided with radial vents 3? to permit ready escapeto the atmosphere of gases which may be generated as an incident to theoperation of 'the' circuit interrupter 25.

Threaded on and depending from the underside of the conducting member 26is an insulating arcing tip 43 of the insulating sleeve 38 and threadedinto the underside of the conducting member- 26 is a conductingsleeve lil of copper' oi brass. The lower enema of the conducting.sleeve-fisconstitutes an annular relatively stationary contact'which hasa radially inwardly directed shoulder- 4| the: purpose of which willbedescribed presently. At the lowerconducting sleeve 39 there is provideda ringhke'arcing:contact. Immediately below the: arcing contact 42 is.an arcing tube which preferably is formed of'light transmittting arcextinguishing material such as methylmethacrylate resin. The reason foremploying this material isto permit the arc-drawn from the arcingcontact 12 to be visible exterior to theinsulating sleeve 33. Thematerial. specified has arc extinguishing properties when it issubjected to theheat of the arcso that it evolves an arc extinguishinggaseous medium which assists in deionizing thearc space and preventingthe arcfrom restriking. Since this construction makes it possible toview the are and to note that it has beendrawn and extinguished; itserves to positively indicate to the lineman that the current carryingcircuit has been interrupted. The lower end of the arcing tube 53 bearsagainst a shoulder 44 formed in the insulating sleeve 33 and istherebyheld in fixed position against endwise movement.

Slidahly mounted within the insulating sleeve 38 is a rod-likerelatively movable contact that isdesignated, generally, at 4?. At itsupper end. the rod-like contact 4? has arms which form a bifurcated endportion having at their extreme upper ends semicircular arcing tips t9which, as shown in Figure 7, are arranged to have contact engagementwith the annular relatively stationary contact is at the lower end ofthe conducting sleeve as. Underneath each semicircular is a shoulder 59which is arranged to bear against the shoulder 4! and thus irictionallyhold the'rod-like contact 4'! against endwise movement through theinsulating sleeve Stunt-ii sufiicient force is exerted thereon toovercome the restraining force provided by the interaction of theshoulders A! and 50.

With a View to holding the semicircular arcing tips 48 in mechanical andelectrical contact engagement with the annular relatively stationarycontact '49, the arms 58 are formed of resilient material and are soconstructed as to he inherent ly biased away from-each other.Additionally a coil compression spring I,-Figure 8, is provided forbiasing-the upper ends: of the arms 68 apart. The coil compressionspring 51 is located in a transverse opening 52in a rod 53 to the upperend of which a trailer {i l is connected. It will be understood that thetrailer 54, which is formed of insulating arc extinguishing mateial,such as methyl -methacrylate resin, is movable together with therod-like contact l! into the bore in the arcing tube 43 for assistingthesame in extinguishing the are drawn between the arcing contact 42.and the semicircular arcing tips 13. At its lower end the rod 53 ispivoted at. 55. to the upper end of a support rod 55 that forms-a partof the rod-like movable contact 4?. At its lower .end the support rod.55 hasa head 51. suitably secured thereto. Between the lower endv of thearcing tube. 43 the upper side ofthe-head 57 a coil compression spring53 is stressed. flfhe spring dais so designed that, by itself, itdoesnot have sufficient power to "disengage the shoulder -50 from theshoulder 4 'ment-of the rod-like contact 47 is limited by a scoped overtheinsulating sleeve 50 :from" the shoulder 41. Accordingly, theseshoulders"Mand SWare'sufiicient to hold the rod-like contact 41 in theclosed position against the biasing'force exerted by the coilcompression spring 58 until some additional force is applied addition tothe force exer-ted' by-the spring 58; todisengage the shoulder I. Thedownward movetubular stop member 59 mounted in a suitable the lower endof the insulating sleeve "With a 'view -to operating the rod-likecontact fi'l'from and tothe closed circuit position, there is provided ametallic slee-vetA which is tele- 38 and has a length about equal to onehalf the length thereof. Near-its upper end the metallic sleeve 4carries a spring finger Ei'which-supports a detent or latch 86 thatisarranged to engage a slot 61 so as -to-"hold by'frictional engagementthe sleeve ti in the position shown in Figure? with resp'ect to theinsulating sleeve 38. The lower shoulder 58*0f the s1ot B1 is inclinedso as to facilitate the \vedging' out of the detent or latch 55 from theslot 67 when the metallic sleeve is moved downwardly relative to theinsulating sleeve-38. Spaced downwardly from the upper slot '5'! isa-lower elongated'slot 69 in the outer surface of the insulating sleeve38. The purpose of the elongated slot 89 is to receive the detent olatchfifigas shown in Figure 12, for the-purpose of-holding the metallicsleeve 64 in thelowermost position and against movement upwardly to aposition corresponding to the circuit closed, position of'the contactsand 49. However, the'upper'shoulder 70 of the elongated slot 59 inclinedso as to wedge the detent or latch out of *thesame when suflicientupward force is applied to the metallic sleeve 64 for the purpose ofreclosing will hereinafter appear; under certain operating conditions itmay be necessary to move the sleeve fiedownwardly past the-positionshown in Figure It is 'for this-reason that the slot 59 is elongated soas to permit such movement of the detent-or latchSS.

There is a 'lost motion connection provide-cl between the metallicsleeve 64 and the rod-like contact 41. *In part this lost motionconnecticn'is made up of a-longitudinal slot 'il in the metallic sleeve54 and an arm [2 projecting from the head"?! through a longitudinal slot13 in the "insulating "sleeve 38. Contact fingers l4, carriedby"thej-projecting"end of the arm 12, bear against the outer surface ofthe metallic sleeve 54, as shown 'in Figure 10, for the purpose01..maintaining good "circuit connection between'themetallic' sleeve 54and the rod-like contactd'l. Theupper end 15 of the slot H is arrangedto engage 'theinpper'side of the arm 1'2 when the sleeve 641s moveddownwardly relativelytothe' insulating sleeve 38. and continued movementof the sleeve causes the shoulder 50 to disengage the shoulder ii on theannular stationary contact 4!) so as to permit the spring 53 to move therod-like contact 4'! to the'open position. "Whenlthe rod-like contact 4!is to he. returned to the closed position, the metallic sissy-e754 is.moved upwardly, from the position shown in Figure 12;.and'the lowerendlii of the slot 1! engages the underside of'ithe' arm '72 to move/thecontact. upwardly and to compress the spring58. It' will be understoodthat the sleeve 54 is moved upwardly sufficiently far so as to cause theshoulder 50 to override the shoulder 49 and restore the rod-like contact4'! to the position shown in Figure 7.

With a view to moving the metallic sleeve 64 relative to the insulatingsleeve 38 for the purpose of effecting operation of the rod-like movablecontact 41 into and out of engagement with the annular stationarycontact 49, a support bracket 8! is provided, Figure 8, and it is formedof a split construction with spaced ends 82 that are adjustablyinterconnected by a bolt 83. The support bracket 8| preferably is formedof good conducting material such as brass or copper and, as shown inFigure '7, is located intermediate the ends of the metallic sleeve 64and is rigidly clamped thereto so as to have good electrical contactengagement therewith. The reason for this is that the support bracket 8|forms a part of the circuit through the auxiliary circuit interrupter ina manner to be described presently. Since the support bracket 9! ismovable past the contact finger T4, the former is provided with anoffset portion 84 which, as shown in Figure 8, clearly spans the contactfinger i l. and permits relative movement with respect thereto.

When it is desired to employ the auxiliary circuit interrupter 25 as aline tap and to open and close the circuit thereto, a terminal 95 can beemployed and it can be clamped by a bolt 85 to the oifset portion 84 ofthe support bracket 8!. Suitably secured in the terminal 95 is aflexible cable or tap 81 that may be connected to the desired device,such as a transformer or the like, which is to be energized from thecircuit to which the conducting arm 29 is connected. It will beunderstood that the terminal 85 and flexible cable or tap 8! will not beused when the auxiliary circuit interrupter 25 is intended to be usedsolely for the purpose of opening a disconnecting switch or adisconnecting fuse, such as that illustrated at H] in Figure l of thedrawings.

Formed integrally with the support bracket 9! and projecting therefromis an arm 98, Figure 6, which carries a rockable shaft 89 having aflange 99 secured to one end thereof by a transverse pin 91. Interposedbetween the arm 88 and the flange 90 is a centering spring 92, one end93 being anchored to the flange 90 and the other end 9t being anchoredto the arm 88. At its outer end the shaft 89 carries a head 95 to whichis secured a shank 96 of a contact arm 91. It will be noted that theshaft 89 extends transversely to the longitudinal axis of the tubularauxiliary circuit interrupter 25 and that the shank 95 is inclined at anacute angle to this longitudinal axis when the contact arm 91 is free ofengagement of the pull ring 22. The centering spring 92 is arranged tohold the shank 9t and the contact arm 91 in this position. Then when thecontact arm 91 is inserted in the pull ring 22 with the conducting eyemember 29 in engagement with the conducting arm 24, as shown in Figure3, the centering spring 92 causes the contact arm 9? to engage the innersurface of the pull ring 22 under substantial pressure and thus providesgood electrical contact engagement therewith. As the auxiliary circuitinterrupter 25 is operated through the successive stages shown inFigures 4 and 5, the shank 95 is swung further and further away from thecentered position, shown in Figure 7, and thus the contact pressure onthe pull ring 22 correspondingly increases.

Where it is desired to provide additional contact engagement with thepull ring 22, a contact finger 98, Figure 6, can be employed inconjunction with the contact arm 91. It will be observed that thecontact finger 98 has an outturned end 99 which facilitates cooperationwith the pull ring 22. The contact finger 98 is carried by a sleeve I99which is slidably mounted on the shank 96. A coil compression spring l9!urges the sleeve I99 outwardly of the shank and the contact finger 99toward the contact arm 91. The sleeve I00 is guided on the shank 99 by apin I92 extending radially from the shank 96 and projecting through alongitudinal slot I93 in the sleeve Hill.

It is intended that the tubular auxiliary circuit interrupter 25 will bemanipulated by a lineman using a conventional live line stick which isemployed in conjunction with various live line tools for operation inconnection with circuits that are energized. To accommodate such adevice, the arm 88 has an integrally formed depending bracket 19'!specially designed 'for engagement with a detachable fitting N18. Thebracket i9! and fitting E98 are arranged to be clamped together by abolt 99 having a wing nut i it as shown in Figure 6. It will be observedthat the detachable fitting M38 is mounted on the upper end of a liveline stick I l i which ordinarily is formed of food that has beenspecially seasoned and prepared and is carefully tested with respect toits strength and insulating qualities.

In operation the auxiliary circuit interrupter 25, supported by the liveline stick H! is manipulated, as shown in Figure 3, to place theconducting eye member 29 in operative engagement with the transverselyextending conducting arm 24 from the sleet hood 23 and the centact arm9'! is threaded through the opening in the pull ring 22. Where it isdesired merely to make a line tap, the contact arm 9'! will not beinserted in the pull ring 22 and the flexible cable or tap 8! will beconnected by the terminal 95 to the support bracket 8!. In such case theconducting eye member 29 will be applied to the conducting arm 24 withthe circuit interrupter 25 in the open position. Where it is desired toopen a disconnecting fuse or disconnecting switch, the circuitinterrupter 25 will be applied in the closed position.

Assuming that the circuit interrupter 25 has been applied to the circuitisolating device or disconnecting fuse l9, as shown in Figure 3, then apull is exerted by the lineman on the live line stick III to move themetallic sleeve 99 downwardly over the insulating sleeve 33.

With the circuit interrupter 25 in the closed circuit position, thecircuit therethrough can be traced from the conducting arm 2% throughthe conducting eye member 29 to the relatively fixed conducting member25. The circuit extends therefrom through the conducting sleeve 99 tothe annular relatively stationary contact 2-9 and thence to the arms 43of the rod-like movable contact 47. The circuit is carried through thesupport rod 55 of the contact 41, arm 12 and contact fingers M to themetallic sleeve Thence the circuit continues through the support bracket8!, shank 99 and contact arm 9"! to the pull ring 22. In this manner thetermi nal assembly I2, which is relatively stationary, and the fuse tubeterminal assembly it, which is relatively movable, are shunted so thatwhen they separate no arc will be drawn therebetween.

As the metallic sleeve is 'moved downward ly over the insulatingsleeve38,-the detent or latch 66 is cammed out of the slot-61' over theinclined lowershoulder' 68. The continued movement downwardly of'themetallic sleeve 64 over the insulating 'sleeve 38 is accompanied by nomovement of the rod-like contact since-there is the lost motionconnectiontherebetween. The contact fingers l4 bear" against themetallic sleeve 64 with only suiiicien't iorce to maintain Continuedmovement of the metallic sleeve 84. as shown in Figure 11, causes theupper end 75 of the slot ito engage the radially projecting arm 12' soas to move the shoulder 55 on the underside of the semicircular arcingtips 49 out of engagement with the radiallyinwardly directed 'shoulder4lon the annul r relatively stationary contact 40. This is accomplishedby causing the'bifurcated upper end portion or arms 48 of the rod-likemovable contact 4'. to be moved towardeach other. As soon as theshoulder 50 is moved out of frictional en agement with theshoulder M,the cord compression spring 58 then has suflicient power to continue thedownward movement of the rodlike contact 47 so that it moves downwardlythrough the insulating sleeve 38 with a snap action at relatively highspeed; The arm 7?. moves freely downwardly in the slot 13 andindependently of further movement of the metallic sleeve 54;" Thedownward'movement of the metallic sleeve 54 ordinarilycontinues onlyuntil the detent or latch'ttslides over theupper shoulder it and intothe upper end of the slot -69.

Assuming that the "circuit in whichthe device ii! is connected'iscarryingcurrent, thenan' arc will be drawn'betwe'en the semicirculararcing tips 49 and the ring-like arcing contact 42. Such are will bevisible to the lineman on the ground, particularly atnight, sincetheinsulating sleeve 38 and the arcing tube43- both are formed of lighttransmitting material; The are will be extinguished within thearcingtube i3 as the trailer 54 is moved into'the'sarne because the surfacesthereof evolve in an'arc extinguish-' ing medium due to the=heat 'of thearc.

Another indication that'the interrnpter'25 A circuit is provided bythecontact fingers M again being located at the lower end of the slot H.Preferably, they are painted with a contrasting color, such as .red, sothat their position is readily visible. after noting that the arc hasbeen extinguished that the contact fingers 14-are-at the lower end ofthe slot 7! when the metallic sleeve been pulled to the position shownin Figure 12, knows that it is then safe to remove the auxiliary circuitinterrupter 25 permit the circuit isolating device Hi to operate thefullopen position.

The downward movement of therod-like contact 4? is arrested whenithe'head 51 engages the upper end of the stopmem'ber 58L The relativepositions of the parts when the circuit-interrupter 25-is in the openposition is illustrated in Figure 12.

In the event't'hat the coil compression spring SSshouIdbe unable tact 4!downwardly continued downward sleeve 64 with the upper -end--;7;5 oft-he:slot lt in engagement with the arm lz --will cause. thcsrodto move the:rod-like con- The' lineman,

from the arm- 24 in the manner described, movement ofthe metallic likecontact 41 to move shown by the broken lines in Figure 12, the metallicsleeve 64 would be moved well past the lower end of the insulatingsleeve 38. It is for the purpose of accommodating such extended movementof the metallic sleeve 64 that the slot 69 is elongated for the purposeof accommodating the detent or latch 68, and to permit follow throughwithout injury to the sleeve 38 the stop member 59 preferably is formedof resilient material.

As shown in Figure 12, when the circuit interrupter 25 is in the openposition, the upper end of the rod-like contact 4'! is substantiallycloser to the lower end or" the conducting sleeve 39 than is the upperend of the metallic sleeve 64 or the spring finger 65 carried thereby.High voltage stress then is concentrated on the upper end of therod-like contact ii and any restriking that might take place will occurwithin the arcing tube 43 and not externally thereto.

When it is desired to reclose the auxiliary circuit interrupter 25, thelive line stick H i is moved upwardly. When this occurs, the lower end16 of the slot ll engages the underside of the arm 72 and moves therod-like contact 4'! upwardly until the semicircular arcing tips 49engage the ring-like arcing contact 42. Continued upward movement of thelive line stick ill causes the semicircular arcing tips 39 to moveupwardly until the shoulder iii! again engages the radially inwardlydirected shoulder M. This upward movement of the metallic sleeve Ed onupward movement of the live line stick Hi is permitted since the detentor latch is camrned out of the elongated slot $9 by the inclined uppershoulder id.

The current carrying capacity of the circuit interrupter 25 can beincreased by providing shunting contacts between the conducting member23 and the metallic sleeve E54. For example, contact fingers H2 can besecured by screws H3 to the conducting member 25 and their lower ends H4arranged to make electrical contact engagement with the upper end ofthe-metallic When the circuit interrupter 25 is closed, the circuitthrough the movable contact 41' is shunted by the contact fingers H2. Onmovement of the sleeve 65 toward open circuit position, this shuntcircuit is opened and the en'- tire flow of current is through themovable contact 41.

Since certain changes can be made in the foregoing circuit interrupterconstruction-and different embodiments of the invention can be madewithout departing from the spirit and scope thereof, it is intended thatall matter shown in the-accompanying drawings and described hereinbeforeshall be interpreted as illustrative and not in a limiting sense.

What is claimed as new is:

1. A circuit interrupterfor connection to an energized conductor orterminal and adapted to be manipulated by a live line stick comprising,

effecting op'ening and closing of said separable contacts includingmeans providing mechanical connection downwardly from the 11' relativeto said energized conductor or terminal effects operation of saidcontacts, and circuit means connected to the other of said separablecontacts.

2. A circuit interrupter for connection to an energized conductor orterminal and adapted to be manipulated by a live line stick comprising,in combination, a tubular insulating housing, a pair of separablecontacts Within said housing, connector means having a swivel mountingat one end of said housing and connected to one of said separablecontacts and arranged and adapted to be detachably connected to saidenergized conductor or terminal, operating means associated with saidhousing for effecting opening and closing of said separable contactsincluding means providing mechanical connection to said live line stickwhereby movement thereof relative to said energized conductor orterminal effects operation of said contacts, and circuit means connectedto the other of said separable contacts.

3. A circuit interrupter for connection to an energized conductor orterminal and adapted to be manipulated by a live line stick comprising,in combination, a tubular insulating housing, a pair of separablecontacts within said tubular housing, connector means carried by one endof said housing and connected to one of said separable contacts andarranged and adapted to be detachably connected to said energizedconductor or terminal, a metallic sleeve telescoped over said tubularhousing and operatively interconnected with said separable contacts foropening the same on relative movement of said sleeve housing, supportmeans carried by said sleeve for attachment to said live line stick formoving said sleeve, and circuit means connected through said metallicsleeve to the other of said separable contacts.

a 4. A circuit interrupter for connection to an energized conductor orterminal and adapted to be manipulated by a live line stick comprising,in combination, a tubular insulating housing, a pair of separablecontacts within said tubular housing, connector means carried by one endof said housing and connected to one of said separable contacts andarranged and adapted to be detachably connected to said energizedconductor or terminal, said connector means including means forcooperating with said conductor or terminal to resist longitudinalmovement of said tubular housing in either direction, a metallic sleevetelescoped over said tubular housing and operatively interconnected withsaid separable contacts for opening and closing the same on relativemovement of said sleeve and housing, support means carried by saidsleeve for attachment to said live line stick for moving said sleeve,and circuit means connected through said metallic sleeve to the other ofsaid separable contacts.

5. A circuit interrupter for connection to an energized conductor orterminal and adapted to be manipulated by a live line stick comprising,in combination, a tubular insulating housing, connector means carried byone end of said housing and connected to one of said separable contactsand arranged and adapted to be detachably connected to said energizedconductor or terminal, a metallic sleeve telescoped over said tubularhousing and having a lost motion connection with the other of saidseparable contacts for opening and closing the same on relative movementof said sleeve and housing, connecting means electricallyinterconnecting said metallic sleeve and said other contact to maintaina circuit therebetween, support means attached to said position,

sleeve and arranged and adapted to be attached to said live line stickfor moving said sleeve, and circuit means connected to said metallicsleeve.

6. A circuit interrupter for connection to an energized conductor orterminal and adapted to be manipulated by a live line stick comprising,in combination, a tubular insulating housing, a pair of separablecontacts Within said tubular housing, connector means carried by one endof said housing and connected to one of said separable contacts andarranged and adapted to be detachably connected to said energizedconductor or terminal, spring means biasing said contacts apart endwiseof said tubular housing, detent means cooperating with said contacts andacting to hold the same in engagement against the biasing action of saidspring means, a metallic sleeve telescoped over said tubular housing andhaving lost motion connection with the other of said separable contactsfor moving the same to over come the action of said detent meanswhereupon said spring means moves said contacts to open support meanscarried by said sleeve for attachment to said live line stick wherebyrelative movement of said sleeve with respect to said housing iseffected, and circuit means connected through said metallic sleeve tosaid other separable contact.

7. A circuit interrupter for connection to an energized conductor orterminal and adapted to be manipulated by a live line stick comprising,in combination, a tubular insulating housing, a relatively stationaryannular contact coaxially disposed within said housing and having aradially inwardly directed shoulder, a relatively movable rod-likecontact coaxially disposed within said housing and having one endbifurcated with a radially outwardly directed shoulder thereon, the armsof said end of said rod-like contact being biased apart for engagingsaid shoulder on said annular contact to resist endwise movement of saidrod-like contact, spring means biasing said rod-like contact for endwisemovement away from said annular contact and restrained by saidinterengaging shoulders, connector means carried by one end of saidhousing and connected to said annular contact and arranged and adaptedto be detachably connected to said energized conductor or terminal, ametallic sleeve telescoped over said tubular housing and having lostmotion connection with said rod-like contact for moving the same endwiseto disengage said shoulders whereupon said spring means moves saidcontacts to open position, support means carried by said sleeve forattachment to said live line stick whereby relative movement of saidsleeve with res ect to said housing is efiected, and circuit meansconnected through said metallic sleeve to said rodlike contact.

8. The invention, as set forth in claim '7, wherein at least a portionof the tubular housing between the contacts in open position is formedof arc extinguishing light transmitting material to indicate externallythe drawing of an are therebetween and for extinguishing the same.

9. A circuit interrupter for connection to an energized conductor orterminal and adapted to be manipulated by a live line stick comprising,in combination, a tubular insulating housing, a relatively stationaryannular contact coaxially disposed Within said housing and having aradially inwardly directed shoulder, a relatively movable rod-likecontact coaxially disposed Within said housing and having one endbifurcated with a radially outwardly directed shoulder thereon,

accrues,

the arms of said endeof'isaidrodelike contact by one end of said housingand connected to said annular contact and arranged and adapted to .bedetachably connectedto said energizedconductor metallic sleevetelescoped over said in combination, a tubular insulating housing, arelatively stationary annular contact coaxially disposed Within saidhousing and having a radially 11. A circuit interrupter for connectionto an energized conductor or terminal and adapted to be manipulated by alive line stick comprising, in combination, a tubular insulatinghousing, a relatively stationary annular contact coaxially disposedwithin said housing and having a radially inwardly directed shoulden. a,relatively movable rod-like contact coaxially disposed within saidhousing and having one end bifurcated witha radially outwardly directedshouldertthereon, the arms of said end of said rod-likecontactbeingbiased apart for engaging said shoulder on'said annular contact'toresist endwise movement of said rod-like contact,rspring meansbiasingsaid rod-like contact for endwise movement away from.

said annularcontact and restrained by said in terengaging shoulders,connector means/carried by one end of said housing and connected to saidannular contact and arranged and adapted to be detachably connected tosaid energized conductor or terminal, a metallic sleevetelescoped'oversaid,

tubular housing and having lost motionconnece tion with said rod-likecontact, said lost motion connection comprising a longitud nal slot insaid metallic sleeve and an arm projectingradially from said rod-likecontact through said slot with relative movement therebetween beinglimited by the ends thereof, movement of said sleeve in one directionrelative to said housing with one end of said slot in engagement withsaid .arm causing disengagement of said shoulders whereupon said springmeans moves said contacts to open position and movement of said sleeveinthe .opposite direction relative to said housing with the said slot inengagement with said arm causing movement of said rod-likecontact linestick whereby relative movement of said and circuit means connectedthrough said metallic sleeve to said rod-like contact.

12. A circuit interrupter for connection to an energized conductor orterminal and adapted to housing and having one end bifurcated with aradially outwardly directed shoulder thereon, the arms of said end ofsaid rod-like contact being said annular contact and restrained ;by saidinterengaging shoulders, connector means carried connection comprising alongitudinal slot in said metallic sleeve and an arm projecting radiallyfrom said rod-like contact through line stick whereby relative movementof said sleeve with respect to said housing is efiected, and circuitmeans connected to said metallic sleeve.

13. Mechanism for opening a high voltage circuit isolating device suchas a disconnecting fuse, disconnecting switch or the like normallycarrying line current comprising, in combination, an elongated circuitinterrupter having a relatively fixed conducting member at one end forattachment to a stationary energized conducting part of said circuitisolating device and a relatively movable conducting member adapted tobe carried by a live line stick, a contact arm swingably mounted on saidmovable member to rock about an axis transverse to the longitudinal axisof said circuit interrupter and arranged and adapted to engage a movableenergized conducting part of said circuit isolating device, a centeringspring cooperating with said contact arm to bias the same to a positionat an angle to the longitudinal axis of said circuit interrupter when itis out of engagement with said movable energized conducting part, andarranged to exert substantial contact pressure thereon when inengagement therewith and said contact arm is thereby swung toward saidcircuit interrupter, relatively fixed and movable contacts in saidcircuit interrupter connected respectively to said fixed and movableconducting members, movement of said movable conducting member away fromsaid fixed conducting member effecting separation of said movableenergized conducting part from said stationary energized conducting partwhile maintaining a shunt circuit therebetween through said contacts,and operating means responsive to said movement or said movableconductin member away from said fixed conducting member for effectingseparation of said contacts.

14. A circuit interrupter comprising, in combination, a tubularinsulating housing, a relatively stationary annular contact coaxiallydisposed within said housing and having a radially inwardly directedshoulder, a relatively movable rod-like contact coaxially disposedwithin said housing and having one end bifurcated with a radiallyoutwardly directed shoulder thereon, the arms or" said end of saidrod-like contact being biased apart for engaging said shoulder on saidannular contact to resist endwise movement of said rod-lure contact,spring means biasing said rod-like contact for endwise movement awayfrom said annular contact and restrained by said. interengagingshoulders, a sleeve telescoped over said tubular housing and having lostmotion connection with same endwise to disengage said shoulderswhereupon said spring means moves said contacts to open position, andoperating means connected to said sleeve for moving the same relative tosaid housing.

15. The invention, as set forth in claim 14,

wherein at least a portion of the tubular housing between the contactsin open position is formed of arc extinguishing light transmitting saidrod-like contact for moving the.

16 material to indicate externally the drawing of an arc therebetweenand for extinguishing the same.

16. A circuit interrupter comprising, in combination, a tubularinsulating housing, a conductor extending into said housing from one endhaving a relatively stationary contact at its inner end, a relativelymovable contact Within said housing for engaging said relativelystationary contact, spring means for biasing said movable contact forendwise movement through said housing away from said stationary contact,means holding said contacts in engagement, and a metallic sleevetelescoped over said tubular housing and having lost motion connectionwith said movable contact for moving the same endwise to disengage saidcontacts and permit said spring means to move the same apart.

17. A circuit interrupter comprising, in combination, a tubularinsulating housing, a conductor extending into said housing from one endhaving a relatively stationary contact at its innor end, a relativelymovable contact within said housing for engaging said relativelystationary contact, spring means for biasing said movable contact forendwise movement through said housing away from said stationary contact,means holding said contacts in engagement, a metallic sleeve telescopedover said tubular housing and having lost motion connection with saidmovable contact for moving the same endwise to disengage said contactsand permit said spring means to move the same apart, and stop meanslimiting the movement of said movable contact away from said stationarycontact to a position where the distance therebetween is less than thedistance between said stationary contact and said metallic sleeve.

18. A circuit interrupter, comprising, in combination, a tubularinsulating housing, .a conductor extending into said housing from oneend having a relatively stationary contact at its inner end, arelatively movable contact within said housing for engaging saidrelatively stationary contact, a coil compression spring biasing saidmovable contact away from said stationary contact, latch means holdingsaid contacts in engagement against the biasing force of said spring, ametallic sleeve telescoped over said tubular housing and having lostmotion connection with said movable contact for unlatching said latchmeans on movement to a predetermined position along said tubular housingaway from said stationary contact to permit said spring to separate saidcontacts, and stop means limiting the movement of said movable contactaway from said stationary contact to a position where the distancetherebetween is less than the distance between said stationary contactand said metallic sleeve.

SIGURD I. LI ELL.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,239,224 Golden Apr. 22, 1941 2,331,778 Hill Oct. 12, 19432,438,746 Garrison Mar. 30, 1948

